Current collector



May 23, 1950 A. J. MOSLEY CURRENT COLLECTOR Filed Feb. 14, 1949 INVENTORAlfred 4!. Masley /fi/La/ r a ATTORNEYS 7 Patented May 23, 1950 CURRENTCOLLECTOR Alfred J. Mosley, Cleveland, Ohio, assignor to National Bronze& Aluminum Fdry. (30., Cleveland, Ohio, a corporation of OhioApplication February 14, 1949, Serial No. 76,359

Claims. 1

This invention relates to electrical current collecting devices, moreparticularly to slider shoes such as are employed on trolley poles usedon electric busses, street cars, and the like.

Current collectors or slider shoes are replaced or rebuilt from time totime on busses and street cars because of the wear that occurs in use.Such shoes or collectors are designed to minimize wear on the conductorsor trolley wires of transit systems, not only because of the greatexpense involved in replacing trolley wires, but also because of thedisruption to the transit system caused by discontinuance of service fortrolley wire replacement.

It is therefore one of the principal objects of the present invention toprovide a generally improved collector shoe or trolley slide of the typeemploying a suitable wear resistant insert or wire contacting brush, thecollector shoe being simple in design and construction for economicalmass production as by casting so that when renewal is necessary, it isfeasible to replace the entire shoe and discard the worn one.

Another object is to provide a rugged, long wearing collector shoerelatively light in weight and substantially free of internal orstructural strains, such characteristics being achieved withoutobjectionably increasing the relative wear on trolley wires.Preferentially the slider includes a wear insert and a one piece holderor frame cast about the insert, the frame incorporating simple wiper orscraper means to remove objectionable foreign material from trolleywires in advance of the insert, thus preventing the movement of abrasiveparticles between such wires and the wear insert. More specifically, theinvention seeks to provide a unitary slider shoe incorporating anelongated carbon Wear block or brush, preferably of rectangulartransverse section, embedded in a one piece cast metal body or frame ofrelatively lightweight construction.

Another object is to provide a current collector shoe of the carboninsert type suitable for manufacture by high speed casting of lightmetal alloys.

A further object is to provide a lightweight collector shoe capable ofcarrying relatively high energy electrical current without objectionableheating, yet being cheap to make and having a brush insert for longwear.

Other objects and advantages relate to certain details of constructionand combinations and arrangements of parts, as set forth in thefollowing detailed description of the invention made in connection withtheaccompanying drawings forming a part of the specification. Like partsthroughout the several views are indicated by the same numerals ofreference.

In the drawings:

Figure l is a side elevational view, with parts broken away and removed,of the upper or head end of a trolley pole structure showing thereplaceable collector shoe of the present invention mounted thereon;

Fig. 2 is an end elevational view of the collector shoe of Fig. 1;

Fig. 3 is a top plan view of the collector shoe;

Fig. 4 is a transverse sectional view taken substantially on the lineindicated at 4-4 of Fig. l, the trolley pole head being omitted;

Fig. 5 is an elevational view, partly in section and with parts removed,showing a modified form of collector shoe; and

Fig. 6 is an end elevational view partly in section and with partsremoved of the trolley shoe shown in Fig. 5.

The collector shoe or slider of the present invention is suitable formounting on conventional types of trolley poles, a representative andsimplified trolley pole head being shown in Fig. 1. The assemblyincludes a head member l suitably secured on the upper end of thetrolley pole and formed with a yoke or harp 2 which carries a transversepivot bolt 3 for tiltably mounting a. carrier or tilt block 4. Thestructure desirably includes conventional means, not shown, permittingthe slider shoe to turn about a, vertical axis which permits lateral orside to side movement of the trolley pole under the trolley wire.

The replacement shoe or current collector itself comprises an elongatedwear block or insert 5 formed as by pressure molding of carbon orcarbonaceous material of graphitic character. This block may be suitablytreated or impregnated in a conventional manner with the customarymetal, plastic, or other friction reducing and binding materials.Although various cross-sectional shapes may be employed, it ispreferable to make the wear insert of substantially uniform rectangulartransverse or cross section from end to end. Desirably the block is ofgreater height than width for long life.

Mounting the wear insert or carbon element on the top flat surface ofthe tilt block 4 and protecting the carbon element against damage fromshock and impact is a guard frame or body formed, preferably in onepiece, as by casting of a metal such as brass, bronze or aluminum andits alloys. The cast body is designed with particular reference to theshrinkage that occurs in metal such as aluminum, upon cooling from themolten state. Considerable difficulty has been encountered in castingcarbon and graphitic wear inserts in aluand connected as tointerlockingly 1 1a and m; brace the insert do not pose undesirablestresses or forces on such insert upon cooling from the molten state.The cast metal partsor elements comprising the body may be connected,

preferably integrally, by relatively thin portions for embracing andconfining the majorportions of the wear insert.

in contacting relation to the latter for wiping the trolley wire free ofdirt and foreign material in advance of the carbon block. This featureis particularly advantageous in localities Where ice forms on thetrolley wires, since the relatively tough brass or aluminum of the websI! removes depending ice particles in'advance of the more fragile orbrittle carbon block.

Along the sides of the collector relatively thin "web portions 2!]connect the stirrup uprights 6 and v are preferably integral with thelatter.

'These connecting webs are disposed flatwise against the centralportions of the block side faces 9 and maybe smooth surfaced, althoughpreferably they are formed with a multiplicity of relatively thincooling and reinforcing ribs 2|.

A suitable arrangement for the frame comprises a pair of spacedsubstantially U-shaped :stirrupsarranged in parallel relation; each stir:ruphaving uprights Gintegrally connected by bottom or cross elements,1; 'The strirrups receive the ends of the wear block 5; sides 9 of thewear blockatthe ends of the latter being em- 5 braced by the uprightportions 6 of the stirrups; andportions; of bottom 10 of the wear blockat the ends of the latter resting on the'cross or integral connectingportions 1 of V the stirrups. The upper ends of the stirrup'uprights 6are connected, preferably integrally, by longitudinally extending guideelements 8. The guideelements include angularly disposed end portions 1|presenting inclined or sloping edges l2 which aid in moving thecontactorshoe across switches, crossing-plates, and the like. Preferably, theguideelements 8 are divergently arranged above the wear block 5, asshown in Fig. 2, providing a .tapered channel to receive and confine thetrolley wire which is to bereceived and. engaged in groove I9 of thewear block 5. a. r

-:Foreign.material such as dust, dirt and the like, collectingontrolley. wires, is frequently dislodged by current collectors andtrolley shoes moving alongthereunder. 'Such material of a hard Or grittynature, when caught and held in the open topchannel of a collector shoe,is objectionable because of abrasion to'the trolley Wire and to the shoeand interference with elec trical conductivity. The construction ofthepresent collector or trolley shoe leaves substantially the entiremarginor periphery of top sur- ;face 14 of the carbon block 5substantiallyopen and unobstructed laterally so that particles of-foreign material dropping into the trolley wire channel are readilydischarged not only through the relatively narrow channel ends but alsolaterally alongsubstantially the entire length of the carbon block. Inthe present arrangement the guide elements Bare-disposed wholl above theplane or level'of the top M of ,the wear block fprovidingelongatedlateral openings l5 below botto'm edges I 6 of the guideelements. Although these elongated clearance openings may be of lessextent, they preferably are continuous along substantially the majorportion of the upper edge corners of the carbon wear block-or insert.:Across-the ends of the shoe orcollector the stirrup-uprights 6 areconnected as by integral ,relatively-thin webs I! which are disposedflatwise againstend faces [8 of the carbon wear block 5.: Although theendwebs I! may be of any desired height relative to the carbon wear.block, itis preferable to make them of'substan- +tia1lythesame heightas the wear block so as to move along the trolley wire closely adjacentor The ribs 2|, which may be sheet metal inserts or, as shown, castintegrally with the webs and stirrups in the formation of the collectorshoe. extend longitudinally of the side-webs substantially from end toend thereof, being joined or connected to the stirrup uprights 6. In theaggregate, the areas of the block faces contacted by the relatively thinconnecting webs are. greater in extent than the areas contacted by therelatively thick sectioned frame elements.

In mounting the collector or trolley shoe on the tilt block 4 of thetrolley pole, conventional arrangements may be employed. The illustratedarrangement comprises integral ears or lugs 22 and 23 connected to orcast integrally on the bottom cross elements 1 of the frame stirrups.The ear 22 includes an offset portion which is receivable against anundercut face 24 on one end of the tilt block 4. The lug 23 is drilledand threaded to receive an angularly disposed looking screw 25 arrangedto bear against an angularly disposed .face 26 on the other end of thetilt block. When the screw 25 is tightened against the tilt block face,the bottom face H) of the carbon block 5 and bottom edges 21 of the sidewebs 20 are drawn snugly against the flat upper surface of the tiltblock 4, effecting good electrical connection therewith.

In applications requiring the transfer of large electrical currents, thecollector shoe described is particularly advantageous by reason of thecooling action of the ribs or vanes 2| which travel longitudinallythrough the atmosphere. Heat developed in the carbon blocki by reason ofthe conductivity of electrical current therethrough taken up all alongits sides by the closely embracing relatively rapid heat conductingmetal of the cast body and is quickly conducted into the cooling vanes2| for dissipation to the atmosphere. "Thus, overheating of thecarbonand metal .of the'collector shoe is avoided. In applications requiring aless rugged construction, or'where less electrical energy is to beconducted, or where other considerations con- :trol, the modificationillustrated in Figs. 5 and 6 maybe employed. In these figures, parts orcomponents of the structure that are the same as in the embodiment ofFigs. 1 through 4 are indicated by the same reference numerals. The endwebs I 'I are omitted or reduced in height at both ends of the shoe andappear as reinforcing gussets 28 which are preferably cast integrally inthe angles between'the uprights 6 and the cross elements I to reinforcethe stirrups.

In lieu of the thin side webs 20, the uprights 6 are joined by thin,relatively 'low, connecting webs or elements 30 which arepreferably castintegrally with the stirrup uprights 6. While bottom edges 3| of theconnecting elements 39 are straight and substantially flush with thebottom ill of the wear block 5 for contacting the upper surface of thesupporting tilt block 4, upper edges 32 are curved, providingreinforcing gussets 33 integrally joined to the stirrup uprights. Themajor portion of each of the wear block side faces 9 between thestirrups are thus exposed to the atmosphere. Longitudinally extendingribs 36 optionally may be integrally formed along the connectingelements 30, the ends of these ribs being connected to the stirrupuprights 6 and serving not only to reinforce the side structure of theshoe but also to aid in cooling of the shoe.

The opposite sides of the metal holding frames of the slider shoes ofthe present invention are connected only at the ends of the shoes, theentire bottom surface of each of the wear inserts being exposed fordirect bearing contact with the supporting trolley head structure. Thethin sections of the connecting webs permit casting the metal bodiesabout the wear inserts in such a manner that the webs freeze or hardenbefore the heavier sectioned parts of the frame body, thus minimizingstresses imposed on the carbon insert by shrinkage of the cast meal.

In accordance with the patent statutes, the principles of the presentinvention may be utilized in various ways, numerous modifications andalterations being contemplated, substitution of parts and changes inconstruction being resorted to as desired, it being understood that thearticles shown in the drawings and described above are given merely forpurposes of explanation and illustration without intending to limit thescope of the claims to the specific details disclosed.

What I claim and desire to secure by Letters Patent of the United Statesis:

- 1. A current collector shoe comprising an elongated wear block ofsubstantially rectangular transverse section and a metal frame embracingthe block, said frame having elements extending under the block adjacentthe ends of the latter, up the block sides at said ends andlongitudinally of the block spaced above the top of the latter, the topof the block being open along its side edges intermediate the blockends, and metal web portions thinner than the elements disposed fiatwiseagainst the sides of the block and connected to the upwardly extendingelements.

2. A current collector shoe comprising an elongated wear block ofsubstantially rectangular transverse section and a metal frame embracingthe block, said frame having elements extending under the block adjacentthe ends of the latter, up the block sides at said ends andlongitudinally of the block spaced above the top of the latter, the topof the block being open along its side edges intermediate the blockends, and metal web portions thinner than the elements disposed fiatwiseagainst the ends and sides of the block and connected to the upwardlyextending elements.

3. A current collector shoe comprising an elongated wear block ofsubstantially rectangular transverse section and a metal frame embracingthe block, said frame having elements extending under the block adjacentthe ends of the latter, up the block sides at said ends andlongitudinally of the block spaced above the top of the latter, the topof the block being open along its side edges intermediate the blockends, metal web portions thinner than the frame elements disposedfiatwise in heat conducting relation against the block sides, and aplurality of relatively thin metal cooling fins integral with the webportions and extending between and integrally connected to the upwardlyextending elements of the frame.

4. A current collector shoe comprising an elongated wear block havingtop, bottom, end and side faces and a cast metal body embracing theblock, said body including relatively thick sectioned frame elementscontacting the block across the entire width of its bottom face and overthe entire height of its side faces, said body also including relativelythin sectioned web elements contacting the block faces, the areas of theblock contacted by the frame elements being less than the areascontacted by the web elements.

5. A current collector shoe comprising an elongated Wear block havingtop, bottom, end and side faces and a cast metal body embracing theblock, said body including relatively thick sectioned frame elementscontacting the block across the entire width of its bottom face and overthe entire height of its side faces, said body also including relativelythin sectioned web elements contacting the block faces, the areas of theblock contacted by the frame elements being less than the areascontacted by the web elements and spaced from one another by the webcontacted areas.

ALFRED J. MOSLEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 638,047 Dunning Nov. 28, 18992,044,886 Larsson June 23, 1936 2,169,154 Lapham Aug. 8, 1939 2,185,268Ryan Jan. 2, 1940 2,457,326 Sloane Dec. 28, 1948

